In the above described technical field, the electrical generator and in particular the stator and the rotor has to be cooled, in order to optimize its efficiency and achieve the highest possible value of generated electrical power. Various air cooling systems are known in the art for cooling the electrical generator in a nacelle for a wind turbine.
One possibility is to suck the cooling air from the outside and to direct it directly towards the generator. The main inconvenience of such solution is the moisture and salt content in the outside air, which causes corrosion in the generator, thus limiting its life. To avoid such inconvenience, a cooling circuit using the air already present inside the wind turbine may be formed. The efficiency of such solution may be however lower than the efficiency obtainable by using air from the outside ambient.
Cooling arrangements according to the above described prior art are shown in US 2017/074251 A1 and in EP 2 182 629 A1.
There may be therefore still a need for providing a new nacelle including a cooling circuit for improving the cooling of the electrical generator, in terms of efficiency and the durability of the components inside the nacelle, in particular the generator.